Updated at 1:51 a.m. ET
(CBS/AP) WOODWARD, Okla. - The television was tuned to forecasters' dire warnings of an impending storm when Greg Tomlyanobich heard a short burst from a tornado siren blare after midnight Sunday. Then silence. Then rumbling.
The 52-year-old quickly grabbed his wife and grandson, hurrying them into the emergency cellar as debris whirled around their heads at their mobile home park in northwest Oklahoma. They huddled inside with about 20 other people before the tornado among dozens that swept across the nation's midsection during the weekend roared across the ground above, ripping homes from their foundations.
"It scared the hell out of me," Tomlyanobich said.
The storm killed six people, including three children, and injured more than two dozen in Woodward, a town about 140 miles northwest of Oklahoma City. But it was the only tornado that caused fatalities. Many of the touchdowns raked harmlessly across isolated stretches of rural Kansas, and though communities there and in Iowa were hit, residents and officials credited days of urgent warnings from forecasters for saving lives.
When Tomlyanobich emerged from the underground shelter after the storm subsided, he saw a scattered trail of destruction: home insulation, siding and splintered wood where homes once stood; trees stripped of leaves, clothing and metal precariously hanging from limbs.
"It just makes you sick to your stomach. Just look at that mangled steel," he said Sunday, pointing to what appeared to be a giant twisted steel frame that had landed in the middle of the mobile home park, which is surrounded by rural land dotted with oil field equipment.
The storms were part of an exceptionally strong system tracked by the National Weather Service's Storm Prediction Center in Norman, Okla., which specializes in tornado forecasting. The center took the unusual step of warning people more than 24 hours in advance of a possible "high-end, life-threatening event."
Center spokesman Chris Vaccaro said the weather service received at least 120 reports of tornadoes by dawn Sunday and was working to confirm how many actually touched down.
The storm system was weakening as it crawled east and additional tornadoes were unlikely, though forecasters warned that strong thunderstorms could be expected as far east as Michigan. So far, no other state has reported damage similar to that seen in Oklahoma.
Woodward suffered the worst of the destruction from the storms, which also struck in Kansas, Iowa and Nebraska. Woodward City Manager Alan Riffel said 89 homes and 13 businesses were destroyed, and bloodied survivors in the 12,000-resident town emerged to find flipped cars and smashed trailers.
Retired firefighter Marty Logan said he spotted the tornado when it knocked down power lines, causing flashes of light, and saw a radio tower's blinking lights go black. He later saw a man emerge from a twisted, wrecked sport utility vehicle that had been tossed along the side of the road.
"The guy had blood coming down his face," Logan said. "It was scary, because I knew it was after midnight and a lot of people were in bed."
The state medical examiner's office identified the victims as Frank Hobbie and his 5-year-old and 7-year-old daughters, who died when the tornado hit the mobile home park, and Darren Juul and a 10-year-old girl who died when the home they were in a few miles away was hit. Office spokeswoman Amy Elliot said no other details were available, but she said a critically hurt child was air lifted to a Texas hospital.
CBS News confirmed that a sixth victim, Steven Peil, 63 and a military veteran, also died from tornado injuries sustained at a Woodward mobile home park. He and his wife, Kathe, were air lifted to Amarillo, Texas. She is being treated for a broken shoulder.
Authorities said a signal tower for Woodward's tornado sirens was struck by lightning and hit by a tornado early Sunday morning. Police Chief Harvey Rutherford said the tower that was supposed to send a repeating signal to the town's tornado siren system was knocked out.
Considering the tornado struck at night and the sirens were damaged, it was remarkable that there wasn't a greater loss of life, Rutherford said. "We had the hand of God take care of us," he said.
Frank and Treva Owens knew dangerous storms were moving toward Woodward, and although they didn't hear sirens, the elderly couple was watching TV weather reports all day.
"I heard them say we had nine minutes and that's when I hit the cellar," Frank Ownes said, noting that the 12-foot by 12-foot shelter was prepped with their medications, food and clothing.
Oklahoma Gov. Mary Fallin toured the area by helicopter before walking through some of the town's hardest hit neighborhoods.
"Getting the response out immediately throughout the community it's just remarkable what you have done," Fallin told a group of emergency officials. "Once again that emphasizes how important it is to have a plan."
In the tiny western Iowa town of Thurman, piles of toppled trees lined the streets in front of homes where missing walls and roofs exposed soaked living rooms. Longtime resident Ted Stafford recalled feeling his home shake, then hearing three windows shatter as the storm hit. He was amazed that no one in town was seriously injured.
"We're all OK, fortunately. Nobody's hurt. We can fuel this recovery with beans and coffee," the 54-year-old said while standing on the broken concrete of what had been his home's new basement foundation.
In Kansas, a reported tornado damaged McConnell Air Force Base and the Spirit AeroSystems and Boeing plants in Wichita late Saturday. Preliminary estimates suggest damages could be as high as $283 million in the area, where the storm also toppled a 65-foot Ferris wheel at a local amusement park.
Kansas Gov. Sam Brownback acknowledged that the damage could have been far worse, noting in an interview with CNN that residents appeared to have heeded safety warnings. "God was merciful," he said.
Yvonne Tucker rushed to a shelter with about 60 of her neighbors at Pinaire Mobile Home Park in Wichita. She said people were crying and screaming, and the shelter's lights went out when the twister hit. When they went back outside, they found several homes destroyed, including Tucker's.
"I didn't think it was that bad until I walked down my street and everything is gone," Tucker said. "I don't know what to do."
Fellow mobile home resident Kristin Dean, who was pushed out of her home in a wheelchair, grabbed some possessions before going into the shelter, and she later learned that was all she had left. Her home was gone.
"It got still," she said. "Then we heard a 'wham,' things flying. Everybody screamed, huddling together. It is devastating, but you know, we are alive."